Remove using namespace std;

For historical reasons we had a "using namespace std;" in port.h. This
is generally a bad idea. So removing it and along the way doing a bunch
of cpplint cleanup.

Change-Id: Ia125601a55ae62695e247fb0250df4c6f86c46c6
diff --git a/internal/ceres/dynamic_autodiff_cost_function_test.cc b/internal/ceres/dynamic_autodiff_cost_function_test.cc
index 42d6ab7..4e4faf9 100644
--- a/internal/ceres/dynamic_autodiff_cost_function_test.cc
+++ b/internal/ceres/dynamic_autodiff_cost_function_test.cc
@@ -39,6 +39,8 @@
 namespace ceres {
 namespace internal {
 
+using std::vector;
+
 // Takes 2 parameter blocks:
 //     parameters[0] is size 10.
 //     parameters[1] is size 5.
@@ -212,7 +214,7 @@
   }
 }
 
-TEST(DynamicAutodiffCostFunctionTest, JacobianWithSecondParameterBlockConstant) {
+TEST(DynamicAutodiffCostFunctionTest, JacobianWithSecondParameterBlockConstant) {  // NOLINT
   // Test the residual counting.
   vector<double> param_block_0(10, 0.0);
   for (int i = 0; i < 10; ++i) {